Chloral copolymers

ABSTRACT

Chloral is copolymerized with one or more isocyanate, isothiocyanate, diisocyanate, diisothiocyanate or ketene compounds to produce copolymers which are nonflammable and which can be made into a variety of useful, shaped objects. The process of making the copolymers involves preparing a homogeneous mixture of monomers and polymerization initiator at a temperature above the threshold polymerization temperature of the mixture, cooling the homogeneous mixture below the threshold polymerization temperature and maintaining the homogeneous mixture quiescent during the polymerization.

United States Patent [191 [111 3,917,546 V gI Nov. 4, 1975 CHLORAL COPOLYMERS [58] Field of Search 260/64, 67 R, 2.5 F 75 Inventor: 0&0 F. Vogl, Wilmington, Del. [73] Assignee: E. I. Du Pont de Nemours & [56] References Cited Company, Wilmington, DeL UNITED STATES PATENTS 3,183,213 5/1965 Van Lohuizen et al7 260/67 R [22] 1973 3,254,052 5/1966 McCain et al. 260/67 R 21 Appl. 352 3 7 3,787,366 1/1974 Vaughn 260/64 Related Application Data Primary Examiner-Lucille M. Phynes [60] Division of Ser. No. 227,684, Feb. 18, 1972, Pat, No. Attorn y, Ag nt, or Firm Anth0ny P. Mentis 3,775,371, which is a division of Ser. No. 886,739, Dec. 19, 1969, Pat. No. 3,668,184, which is a continuation-in-part of Ser. No. 731,622, May 23, [57] ABSTRACT 1968, abandoned, which s a 00minnation-impartof Chloral is copolymerized with one or more isocyanate, P 1969, abandoned, Winch isothiocyanate, diisocyanate, diisothiocyanate or kegg g z of June tene compounds to produce copolymers which are a an one nonflammable and which can be made into a variety [52] U S Cl 260 5 117/124 8 117/126 GR 'of useful, shaped objects, The process of making the i 260/2'9 260/3O4 26051 copolymers involves preparing a homogeneous mix- 260/3'1 8 B1 F 260/32 ture of monomers and polymerization initiator at a 2%)0/37 8 260/33 2 260/33 f temperature above the threshold polymerization tem- 26O/33 m 5 260/33 f perature of the mixture, cooling the homogeneous 260/37 26067 6 5 26'0/45 mixture below the threshold polymerization tempera- NZ 26O/459 26O/6'7 R 26O/67 ture and maintaining the homogeneous mixture quies- 260/96 R 26O/585 cent during the polymerization. [51] Int. Cl. C08J 9/00; COSG 6/00; COSG 2/18 31 Claims, No Drawings 1 CHLORAL COPOLYMERS This application is a division of my copending application Ser. No. 227,684 filed Feb. 18, 1972, now U.S.

Pat. No. 3,775,371 granted Nov. 27, 1973, which is a division of my application Ser. No. 886,739 filed Dec. 19, 1969, now US. Pat. No. 3,668,184 granted June 6, 1972 which is a continuation-in-part of my application Ser. No. 731,622 filed May 23, 1968, which in turn was a continuation-in-part of my applications Ser. No. 580,217 filed Sept. 19, 1966, and Ser. No. 558,631 filed June 20, 1966, the last three of which are now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a new class of copolymers of chloral with at least one isocyanate, isothiocyanate, diisocyanate, diisothiocyanate or ketene and process for their preparation.

2. Description of Prior Art Applicants patent U.S. Pat. NO. 3,454,527 issued July 8, 1969, discloses homopolymers of chloral prepared by a process which involves preparing a uniform mixture of chloral and polymerization initiator at a temperature above the threshold polymerization temperature of the mixture, cooling the uniform mixture below the threshold polymerization temperature, and maintaining the mixture quiescent during the polymerization.

US. Pat. No. 3,265,665 issued to Mantell et al. on Aug. 9, 1966 discloses copolymers of formaldehyde and isocyanates by a polymerization process which involves cooling to low temperatures. Chloral is not disclosed nor suggested and quiescent conditions are not maintained during the polymerization process.

Takida et al., Kobunski Kagaku (Chemistry of High Polymers, Japan) 22, 463-472, July 1965, show the co- ,polymerization of chloral with phenyl isocyanate at low temperatures but do not use quiescent polymerization conditions. Their process produced only crumbly, powdery products.

DESCRIPTION OF THE INVENTION This invention is directed to addition copolymers of chloral and at least one comonomer selected from the group consisting of 'wherein, (I) (II) (III) X is selected from the group consisting of oxygen and sulfur;

R and R alike or different and separately or jointly, are selected from the group consisting of (1) monovalent groups selected from the group consisting of hydrogen, cyano, lower alkoxycarbonyl, and unsubstituted and substituted hydrocarbyl and hydrocarbyloxy in which any hydrocarbyl moiety is of 1-18 carbon atoms selected from the group consisting of alkyl, cycloalkyl, aryl, aralkyl and alkaryl, and any substituent is selected from the group consisting of lower alkoxy, fluorine, chlorine, bromine, and iodine; and (2) divalent groups selected from alkylene of 2 to 7 carbons;

R is selected from the group consisting of non-substituted and substituted alkyl and cycloalkyl of up to 18 carbons, aryl of 6-118 carbons and alkaryl and aralkyl of 7-24 carbons, any substitution being selected from the group consisting of fluorine, chlorine, bromine, iodine, nitro, cyano, phenylazo, NY OY, -SY,

in which Y is lower alkyl or phenyl; and

R is selected from the group consisting of non-substituted and substituted alkylene, alkarylene, aralkylene, cycloalkylene, alkylenebis(cycloalkylene), alkylenebis( arylene), arylene, arylenebis- (alkylene) of up to 18 carbons and anthraquinonylene, any substitution being selected from the group consisting of fluorine, chlorine, oromine, iodine, nitro, cyano, phenylazo, NY OY, SY,

ll 11 C-OY and. C-NY in which Y is lower alkyl or phenyl.

Either one or a plurality of ketenes, isocyanates, isothiocyanates, diisocyanates, and/or diisothiocyanates may be reacted with chloral.

In the above definition of R and R preferred hydrocarbyl moieties are alkyl of 1 to 18 carbon atoms, cyclolower alkyl, phenyl, naphthyl, benzyl, tolyl, mesityl and duryl.

As illustrated below, the hydrocarbylene or substituted hydrocarbylene group R may involve aliphatic, cycloaliphatic, and aromatic structures with the two isocyanate or isothiocyanate groups stemming from aliphatic or aromatic carbon atoms. The R, R R and R structures pass unchanged through the polymerization reaction.

The ketene copolymers of this invention are addition polymers which may generally be represented by formula IV b lOO-b c -c (VI) in which b and c represent the mol percentage of chloral units and lOO-b and 100-0 represent respectively the mol percentage of isocyanate and diisocyanate units in the copolymer, and R and R are as defined above. Each copolymer molecule contains at least four chloral units.

It will be understood that more than one compound of formulas I, II and Ill can be polymerized with chloral in the process of this invention. The invention thus includes an addition copolymer of chloral and at least one comonomer selected from at least two of the groups or formulas, I, ll and Ill.

The ketene, isocyanate, isothiocyanate, diisocyanate and diisothiocyanate copolymers of this invention also include branched and crosslinked products in which both N=C=X groups of compounds of formula III polymerize with chloral to form network structures, for which no simple recurring structural formula can be drawn. The copolymers of this invention contain from 1 to 99.9 mol percent of chloral and in general have better thermal stability than polychloral. Copolymers having about 50 to 99.9 mol percent of chloral are a preferred class. Even more preferred are copolymers having about 80 to 99.9 mol percent of chloral. The copolymers may range from soluble, fusible products to ingredients used and their proportions.

Copolymers containing from about 80 up to 99.9 mol percent of chloral and a corresponding 0.1 to about 20 mol percent of comonomer are usually insoluble in common organic solvents such as methanol, ethanol, acetone, benzene, toluene, chloroform, carbon tetrachloride, tetrachloroethylene, ethyl acetate, etc., and are substantially infusible at temperatures up to their decomposition point. Where the chloral content of the copolymer is below about 80 mol percent the products are generally soluble and fusible. It is to be noted however, that the 80 mol percent of chloral content does not always form the line of demarcation. The specific comonomer used, that is, isocyanate, ketene, diisocyainsoluble, infusible products depending on the specific nate, etc. has an effect on the characteristics of the final polymer. For example in chloralisocyanate copolymers having less or more than 80 mol percent of chloral, some may be soluble and infusible, or fusible and insoluble, depending on the particular comonomer isocyanate used to make the copolymer.

the process of preparing the copolymers comprises cryotachensic polymerization. This involves forming a homogeneous mixture of the monomers, an anionic polymerization initiator, and to 99% by weight of the total composition of an aprotic solvent, at a temperature above the threshold polymerization temperature of the mixture, cooling the homogeneous mixture below the threshold temperature whereby polymerization occurs, and maintaining the mixture at such lower temperature until polymerization subsides. A critical aspect is that the polymerization mixture is undisturbed, that is, it remains quiescent during polymerization whereby the mixture initially forms a continuous gel which ultimately converts to high polymer. If the mixture is disturbed or agitated during polymerization, the resultant polymer has diminished strength, toughness and infrangibility.

The cryotachensic polymerization process generally involves preparing a homogeneous mixture of the monomers and polymerization initiator and copolymerizing the monomers simultaneously by cooling. It is to be understood however that the process also includes partial polymerization of chloral alone, followed by reaction with the other comonomers. In this variation of the process a uniform mixture of only chloral and polymerization initiator, with or without aprotic solvents, is prepared ata temperature above the threshold polymerization temperature of the mixture. The mixture is then cooled below its threshold polymerizatioon temperature under. quiescent conditions to partially polymerize the chloral to polychloral. The other comonomer or comonomers are then added to the reaction vessel and caused to copolymerize with chloral under conditions which may be quiescent or not. It is believed the added material copolymerizes not only with the remaining free chloral but also forms block copolymers with the polychloral.

The initiator is always uniformly distributed in the monomer mixture before any polymerization occurs. Thus, when polymerization is brought about by cooling the composition below the threshold polymerization temperature, the composition generally becomes gelled and unflowable within one minute or less. The degree of conversion of monomers to copolymer increases "with time but generally is substantially complete within one hour. The order of addition may be varied but in general the initiator is preferably added after the addition of solvent, if any is used; or the initiator may be added in solution.

The threshold polymerization temperature of a polymerization mixture containing monomeric chloral, one or more ketenes and/or one or more isocyanates, isothiocyanates, diisocyanates or diisothiocyanates and an initiator, and optionally a solvent, is determined as follows: The mixture is prepared and thoroughly blended at an elevated temperature, for example, at its reflux temperature or at 65C., whichever is lower. The mixture is then stirred and cooled at a rate of 2C./min., the stirring being conducted to insure uniform cooling of Y the entire mass of liquid. The threshold polymerization temperature is that temperature at which there is noted the first haziness of opalescence due to solid copolymer separating in the mixture.

The monomer-initiator-solvent compositions have threshold polymerization temperatures in the range from 0-60C. The threshold temperature is affected by both the nature and the amount of ketene, isocyanate,

isothiocyanate, diisocyanate or diisothiocyanate como- Copolymerization of the monomers in the polymerization mixture can be conducted at the threshold polymerization temperature. However, the heat of polymerization is most readily dissipated and the toughness and molecular weight of the polymer are increased if a pol- 1 ymerization temperature of at least 5C. below the threshold polymerization temperature is used, and preferably the temperature is at least 25" c. below and still more preferably, at least 50 to 135C. below the threshold polymerization temperature. Cooling to the desired low temperature may be accomplished by any means known to the art..The cryotachensic polymerization process can be carried out in the presence of air. However, it is preferred to use an atmosphere to which the monomers and the initiator are inert. Thus, it is desirable to exclude moisture, oxygen, carbon dioxide, acidic or basic vapors, and vapors of protic solvents. An inert atmosphere is preferred when pure monomers are to be held for substantial lengths of time prior to polymerization and is particularly advantageous when it is desired to hold a mixture containing the monomers and a polymerization initiator above the threshold polymerization temperature of the composition for more than a few minutes. An inert atmosphere may be obtained by operating at reduced pressures, by operating in nitorgen, helium, or the like, or by other means known in the art.

It is preferable to bring about polymerization by cooling the polymerization mixture below its threshold temperature within a short time after contact of the initiator with the monomers. For example, it is preferable to carry out polymerization within one hour. after contact of monomers with the catalyst and more preferably within ten minutes or less.

Polymerization initiators suitable for use in the present process are essentially those of my previously mentioned coassigned applications Ser. Nos. 580,217, 558,631 and 731,622, and include all of those known to initiate anionic polymerization. Effective initiating amounts of initiator are generally between 0.001 and of the combined weight of chloral and comonomer(s); preferred amounts are 0.005 to 5% by weight. Many of the initiators are Lewis bases. Examples of initiators include: (a) tertiary organic compounds of elements of Group V-A of the Periodic Table, i.e., compounds QR where Q is N, P, As, Sb, or Bi, and R is a hydrocarbyl group containing 1-18 carbon atoms with the proviso that when Q is N, no more than one R can be aryl. The R groups may be alike or different and can be taken together to indicate the hydrocarbon part of a cylic 5- to 7-membered ring system in which Q is a heteroatom as in pyridine, substituted pyridines such as trimethylpyridine, quinoline, triethylenediamine, and alkyl, aryl and benzo derivatives of such compounds. Thus the hydrocarbyl groups may be alkyl as in methyl, ethyl, dodecyl and octadecyl, akenyl as in 9-octadecenyl, aryl as in phenyl, naphthyl, anthryl and benzanthryl, cycloalkyl as in cyclopropyl, cyclopentyl, cyclohexyl and cycloheptyl, aralkyl as in benzyl and phenethyl, alkaryl as in tolyl and xylyl; and the like; ([9) onium, particularly ammonium, phosphinium and sulfonium fluorides, chlorides, bromides, iodides, hydroxides, alkoxides, thialkoxides, carboxylates, cyanamides, cyanates, thiocyanates and azides. The onium cations may be hydrocarbyl substituted, the hydrocarbyl groups being as described for the first group of initiators; (c) Group IA, Group IIA, or Group IIIA metal hydrides, hydroxides, halides, alkyls, alkoxides, carboxylates, cyanamides, cyanates, thiocyanates, and azides, and particularly lithium chloride and similar halides; and (d) phosphine and phosphonium compounds wherein the phosphorous atom carries one or more substituents such as: hydrocarbyl groups (as described under (a) above for the first group of initiators); hydro- 6 carbyl groups containing halogen; and hydrocarbyl groups and halogenated hydrocarbyl groups connected to P through oxygen or sulfur. The Periodic Table re ferred to herein is that set forth in Demings, General Chemistry, John Wiley and Sons, lnc., New York, 5th Edition, 1944, Chapter 11.

The aprotic solvents, when. used as reaction media, must be unreactive with the monomers and the initiator and preferably should be good solvents for each. The resulting polymerization mixture must be homogeneous at the threshold polymerization temperature. Aromatic and aliphatic hydrocarbons, as well as others,.nitriles and ketones, are preferred. Toluene is particularly preferred. Halocarbons such as carbon tetrachloride, esters and amines such as N,N-dimethylformamide and N,N-dimethylacetamide are operable if the polymerization is carried out within less than one hour and particularly less than a few minutes after mixing of the monomers with the solvent and initiator. Specific solvents suitable for use in the polymerization according to this invention include benzene, n-hexane, cyclohexane, diethyl ether, anisole, acetone, cyclohexanone, methyl ethyl ketone, ethyl acetate, acetonitrile, nitrobenzene, methylene chloride, chloroform, tert-butyl chloride, dimethyl sulfoxide, tetramethylurea, hexamethylphosphoramide and the like. Amounts of aprotic liquid up to 10% by weight aid in solubilizing the initiator in-the monomers. High concentrations of aprotic liquid can assist in the application of the unpolymerized mixture as a paint, or for dipping, impregnating and coating operations prior to cooling to bring about polymerization. 0

With initiators which are readily soluble in the warm monomer mixture, no added liquid is required for dispersing purposes. A small amount of such liquid, however, may be desirable to permit shrinkage of the bulk copolymer by evaporation of the liquid after polymerization. This is sometimes useful, in providing for removal of complicated solid shapes from the molds in which they are prepared.

The polymerization mixture can be prepared in the .moldin which the polymer is to be formed or the mixture can be prepared in another container and then transferred to the mold which is ata temperature above the threshold polymerization temperature and which is then cooled therebelow to bring about polymerization.

The compositions are useful either as unfilled compositions or filled compositions containing up to about by weight of a filler or reinforcing agent. All filler types known in the polymer .art, whether inorganic or oganic, may be used. Included are pigments; glass in the form of flakes, fibers, filaments, fabrics, roving, mat, powder, hollow fibers, glass balloons and the like; carbon in the form of carbon black, fibers and graphite; silicas such as diatomaceous earth, fibrous quartz, pulverized quartz, ground silica and pyrogenic silica; boron and metals in the form of a powder, wool or fiber including iron, steel, aluminum, bronze, copper, lead, silver, gold and the like; metal oxides such as iron oxide, alumina, titania, alumina fibers or whiskers, sapphire whiskers, titania whiskers, and the like; salts such as calcium silicate, talc, clays, mica, calcium carbonate, barium ferrite, barium sulphate, boehmite, vermiculite, molybdenum disulfide, asbestos, fibrous barium sulfate, calcite, and the like; dyes; fibers derived from natural or synthetic sources including wool, nylon, polyacrylonitrile, polyethylene terephthalate, polypropylene, polypivalolactone and fluorocarbon plastics 7 such as powder and fibers of polytetrafluoroethylene, polychlorotrifluoroethylene and the like; all as well known in the art.

One or more fillers may be mixed with the monomers, prior to or subsequent to the addition of the polymerization initiator, at a temperature above the threshold polymerization temperature of the mixture. The uniform mixture is then cooled below the threshold polymerization as described above.

The products of the invention are resistant to fire and high temperatures and this property makes them especially valuable in applications where resistance to high temperatures is desirable. The products may be used in their filled or unfilled state and because they are machinable, they may be made into a wide variety of durable, heat resistant shaped solids of all sorts such as chess men, dishes, cups, saucers bowls, balls, dolls and toys of all sorts. They can be made as heat and fire resistant: roofing tiles; architectural sheets and panels one inch or more in thickness; house drain gutters; heater housings; motor coil insulation; structural or resilient foams; fibers for fire resistnt cloth, clothing, drapes, rugs and carpets, etc; fibrids for making heat resistant paper; tough films for packaging and wrapping; potting resins for embedding objects of all kinds; etc., etc.

By employing equipment capable of moving the homogeneous polymerizable mixture of monomers and initiator from a temperature zone above its threshold polymerization temperature through a cooling, polymerization zone to a polymer dicharge area, it is possible to carry out the polymerization process on a continuous basis without agitating the polymerization mixture. Continuous polymerization in this manner is suitable for preparing films, sheeting, beading, rods, tubes, pipes and similar shaped objects commonly prepared from other polymers by melt extrusion. Belt casting of transparent sheeting and films is particularly well adapted to this mode of operation.

The internal physical make-up of the shaped chloral copolymers prepared according to this invention is such as to permit ready removal of any solvent or 'unpolymerized monomers by evaporation, extraction or other common means. This same make-up permits ready access to the interior of large moldings by gaseous reagents or solutions of agents for post-treatment or stabilization, or by solvents for removing initiator residues. Post-treatments of the copolymers with ben zoyl chloride, acetic anhydride, and phosphorus pentachloride can be performed.

EMBODIMENTS OF THE INVENTION The following non-limiting examples further illustrate the invention. Parts and percentages are by weight unless otherwise noted.

EXAMPLE 1 Copolymer of Chloral and Phenyl lsocyanate butoxide in 480 ml. of dried toluene. The stirring was discontinued after the mixture had become completely homogeneous and it was determined that its threshold polymerization temperature was 22C. When the mixture became quiescent, that is, was no longer in an agitated state, the flask containing the quiescent mixture was cooled down to and held at 78C. for 16 hours while maintaining the mixture in its quiescent state. At the end of the 16 hours some of the chloral had homopolymerized to a solid gel. The flask was then connected to anoil pump and held under reduced pressure for a period of 24 hours to remove most of the solvent. During this time the flask and its contents were allowed to warm up to room temperature. ml. phenylisocyanate was added to the flask containing the coalesced mixture of chloral monomer and chloral homopolymer and allowed to react for 16 hours. After that time excess phenyl isocyanate was drained off and the flask broken. The polymer was washed with toluene, and dried. 155 g. of copolymer was obtained in spherical form reflecting the shape of the container in which it was made. Characterization of this polymer by nitrogen analysis (Found: N, 0.89%, 0.99%) showed that 10 mole percent of phenyl isocyanate had copolymerized. The polymer was tough and insoluble in common organic solvents.

EXAMPLE 2 Copolymer of Chloral and Phenyl lsocyanate In a precedure similar to that of Example 1, a mixture of 200 ml. of chloral and 600 ml. of toluene containing 0.27 g. of lithium tert-butoxide (threshold polymerization temperature 30C.) was prepared at a temperature above 30C. The quiescent, homogeneous mixture was cooled down to and held at 78C. for 16 hours. To the resulting gel mixture of polychloral and chloral monomer (aapproximately 30% of the monomer initially charged) was added 100 ml. of a 20% (by volume) solution of phenyl isocyanate in toluene. After 8 hours, solvent and excess phenyl isocyanate were removed under reduced pressure and the product was washed in toluene and dried to obtain 237.5 g. of polymer containing 8 mol percent of copolymerized phenyl isocyanate. This copolymer was also tough and insoluble in common organic solvents.

EXAMPLE 3 Copolymer of Chloral and Phenyl lsocyanate Part A In a dry test tube (18 X 200 mm), which was blanketed with nitrogen, a mixture of 30 g. of freshly distilled chloral and 2.7 g. of freshly distilled phenyl isocyanate was heated in an oil bath to 65C. A 1 molar solution of lithium tert-butoxide 0.4 ml.) in chclohexane was then added. The threshold polymerization temperature of this mixture was 47C. One part of the initiated mixture was left in the test tube until the mixture became quiescent and the tube was then placed without shaking into a "50C. bath. Polymerization commenced almost immediately. The polymerization was essentially complete in 1 hour. The tube containing the copolymer was taken out of the cooling bath and allowed to come to room temperature. The plug of chloral-phenyl isocyanate copolymer was removed from the test tube and washed with carbon tetrachloride. Elemental analysis for C, H, and N (see Table l) indicated that the polymer contained 10 mole percent of phenyl isocyanate. The infrared spectrum showed a strong band at 5.70 ,u indicative of a urethane linkage.

9 Part B The other part of the initiated Comonomer mixture was drawn into a warm syringe and placed between glass plates, separated by a 0.1 mm. gasket, at a temperature above 65C. and allowed to become quiescent. The quiescent mixture was polymerized by cooling the assembly at 50C. for one hour. The resulting film was washed with carbon tetrachloride. A clear film of chloral-phenyl isocyanate copolymer was obtained which was stiff and tough. The polymer was insoluble in common organic solvents. The thermal stability of this sample was substantially improved over the homopolymer of chloral. The weight-loss temperature of the copolymer determined at a heating rate of 6C./min. in nitrogen was 197C. and 200C. in two samples; typical samples of chloral homopolymer had a 5% weight-loss temperature in the range of 85120C.

EXAMPLES 4-40 Similar copolymerizations of chloral were carried out with other isocyanates as comonomers. The procedures 10 of Example 3, Parts A and B, were followed exactly and the results are shown in Table I which follows. In the table the modulus values refer to stiffness or tension.

TABLE I Copolymerization of Chloral with lsocyanates Comonomer Mole Copolymer Mole Chloral Amount Chloral Analysis Chloral Example (ml.) Type (ml.) ln Feed C H N In Polymer 3 20 Phenyl isocyanate 3 88 20.56 1.11 1.13 90 1.15 4 20 Methyl isocyanate 3 80 5 20 n-Butyl isocyanate 3 88.5 17.00 1.05 0.54 95 0.54 6 20 Octadecyl isocyanate 7 90 22.23 2.07 0.61 94 0.61 7 20 Dodecyl isocyanate 5 90 19.88 1.37 0.58 95 0.57 8 20 lsopropyl isocyanate 3 86 16.81 0.75 0.35 97 0.35 9 20 Toluene diisocyanate 3 90 21.27 1.24 2.22 89 2.30 10 20 l-Naphthyl isocyanate 3 86.5 16.96 1.20 0.47 95 0.37 1 1 20 Ethyl isocyanate 3 84 17.65 0.98 0.86 91 0.96 12 10 n-Butyl isocyanate 2.85 80 18.74 1.12 0.86 91 0.91 13 20 n-Butyl isocyanate 2.25 91 17.15 0.91 0.55 95 0.41 14 20 nButy1 isocyanate 1.15 95 17.37 0.89 0.46 95 0.45 15 n-Butyl isocyanate 0.57 97.5 16.77 1.00 0.21 97.5

0.24 16 20 a,a,a',a-Tetramethyl- 3 (g.) 94 15.81 0.86 0.08 99.4

xylylene diisocyanate 0.1 1 17 20 4,4'-diisocyanato- 3 94.5 16.32 0.89 0.25 97.5

dicyclohexylmethane 0.24 18 20 Hexamethylene diiso 3 91 18.83 1.24 1.17 94 cyanate 1.23 19 20 Phenyl isothiocyanate 2.65(g.) 91 16.70 1.24 0.13 98.7

0.13 20 20 n-Butyl isothiocyanate 2 (g.) 92.5 v 0.13 98.7 21 20 Methyl isothiocyanate 1.5(g.) 91 0.19 98.4 22 20 Methyl isocyanate 1 (g.) 93 0.93 91.6 23 2O 2,5-Dichloropheny1 2 (g.) 95 0.36 96 isocyanate 24 20 3,4Dibr0mophenyl 18-) 90 1637 0- 52 95 isocyanate 25 20 pBromopheny1 isocyanate 3.96(g.) 91 0.89 90 26 20 0-Chloropheny1 iso 3.07(g.) 91 0.77 91.6

cyanate 27 20 m-Chlorophenyl iso- 3.07(g.) 91 1.00 89 cyanate 28 20 p-Chlorophenyl iso- 3.07(g.) 91 1.12 87.5 cyanate 29 20 o-Methoxyphenyl iso- 2.98(g.) 91 0.94 90 cyanate 30 2O p-Methoxyphenyl iso- 2.98(g.) 91 1.03 89 cyanate 31 20 o-Ethoxyphenyl iso- 3.26(g.) 91 0.93 90 cyanate 32 20 p-Ethoxyphenyl iso- 3.26(g.) 91 1.01 89 cyanate 33 20 oNitrophenyl iso- 3.24(g.) 91 0.93 95 cyanate 34 20 mNitrophenyl iso- Saturated 94 1.39 93 cyanate solution 35 20 p-Nitrophenyl iso- Saturated 97 1.42 93 cyanate solution 36 20 o-Tolyl isocyanate 2.66(g.) 91 1.28 87.5 37 20 m-Tolyl isocyanate 2.66(g.) 91 0.62 94 38 20 p-Tolyl isocyanate 2.66(g.) 91 0.62 94 39 2O Methylene di-phenyl 3.3 (g.) 87

diisocyanate 2O Octyl isocyanate 3.0 (g.) 92 0.12 98.7

TABLE l-contmued Film Properties, Part B Tensile Strength elongation at modulus Example (psi) Break (psi) 9 5490 9.8 171,000 10 6950 29.3 149,000 I l l 6760 6.0 12 7120 12.3 300,000 13 6870 16.8 221,000 14 7430 16.5 115.00 15 5800 9.3 264,000 16 4610 32.5 181,000 17 5590 23.0

t an o a ue mas r one hour t t tube was al- EXAMPLE 41 0 P q S Afle the es Copolymer of Chloral and Phenyl Isocyanate In a dried test tube, 4 ml. of chloral and 0.4 ml. of phenyl isocyanate were dissolved in 20 ml. of toluene. The resultant mixture was heated to 60C. and 0.12 ml. of l-molar lithium tert-butoxide in toluene was added thereto. The test tube was stoppered and the quiescent mixture was cooled to 20C. The mixture set up in a few minutes to a transparent get. After one hour, the tube was allowed to come to room temperature and to stand overnight. Toluene was partially removed under reduced pressure and the polymer plug was taken out of the test tube. The polymer gel had collapsed and was clear. Toluene and traces of unreacted monomers remaining in the polymer were allowed to evaporate at room temperature in the air. A conherent plug of chloral/phenyl isocyanate copolymer was obtained having the characteristic IR absorption of 5.70 ,u..

EXAMPLE 42 Copolymer of Chloral and Phenyl Isocyanate lowed to come to room temperature. The test tube was opened and some pentane was allowed to evaporate until the polymer shrank from the glass surface. The polymer was removed from the test tube and pentane and unreacted monomers allowed to evaporate completely (oneday). The polymer mass weighed 7.2 g. and had the shape and approximate volume of the test tube. The polmer was cut in half and the cut faces showed the physical structure of a foam of very fine pore size. The density of this foam was 0.35 (as compared to polychloral of 1.9). The infrared spectrum determined on a thin section of the foam showed the characteristic bands of a chloral-phenyl isocyanate copolymer especially the strong urethane band at 5.70 p.

The following example illustrates the variation in characteristics produced by varying the proportions of the reactants.

EXAMPLE 43 Copolymer of Chloral and Phenyl Isocyanate A series of test tubes were charged under nitrogen with chloral and phenyl isocyanate in the amounts indicated below and heated to 60C. To each tube was then added 0.8 ml. of a one molar solution in chloroform of a polymerization initiator, l/l triisopropyl phosphinelchloral salt having the formula to form a homogeneous mixture (see example C below for preparation of this initiator.) After each mixture had become placid it was cooled without agitation 13 to C. and held at that temperature for 16 hours. The data below give the properties of the resultant copolymers.

Charged Nature of Resultant lsolated Ex. Chloral CBHSNCO Material Containing Copolymer 43 ml. m1. mol the Copolymer grams A 11.8 8.7 solid 15.9 B 9.8 11.0 solid 14.7 C 7.9 13.2 solid 12.5 10

D 5.9 15.4 visc., clear 8.8 E 5.9 15.4 70 very visc., clear 9.1 F 4.9 16.5 visc., clear 7.6 G 5.9 17.6 S1. visc., clear 5.5

v n 1 5 Copolymers A, B, and C were ground 1n methanol in a high speed blender. The partilces were then washed thoroughly with methanol, then with acetone, and then dried. Materials D, E, F, and G were dissolved in benzene and then precipitated into a large volume of meth- 20 anol. The resultant particles were washed with methanol, then with acetone, and finally dried.

The isolated polymers showed the following properties:

cium chloride tube. The mixture was heated to 65C. and 15 ml. of a l-molar lithium tert-butoxide solution in cyclohexane was added to form a uniform mixture. The threshold polymerization temperature of this mixture was determined to be 47C. After the mixture became quiescent, the flask and its contents was placed without agitation in a bath at 78C. and polymerization commenced immediately. After 16 hours, the flask was brought to room temperature. The contents had polymerized completely to a bright-red, almost transparent sphere of chloral/butyl isocyanate/phenyl isocyanate/2,4-diisocyanatotoluene copolymer. The blockwas hard and tough, and had the exact shape of the vessel in which it was prepared.

Other examples of the copolymers of this invention are obtained when the following isocyanates, diisocyanates, isothiocyanates and diisothiocyanates are used in place of phenyl isocyanate, as for instance in the procedure of Example 3:

methoxydifluoromethyl isocyanate;

2(4-ethylphenyl) 1,1-dimethylethyl isocyanate;

2-benzo[b]thien-3-yll-metl'nylethyl isocyanate;

1,5-naphthylene diisocyanate;

pbis-( 2-chloroethyl )amino ]phenyl isocyanate;

lnh. Visc.

Wt. Mol 0.5% Cl-lCl Osmotic Molds to Clear Decomp. $01. in

Ex. 43 N C H NCO 25C. Mol. Wt. Film at C. Temp. C. Benzene A 0.98 10.3 No 270 No B 1.19 12.2 No 250 No C l .47 15.0 No 270 Partially D 2.00 20.2 0.15 94,300 Yes E 1.70 17.2 150,900 No 280 Yes F 1.84 18.8 68,600 Yes G 2.04 22.2 67,100 280-290 300 Yes Copolymer C contained a little soluble polymer. A 3-g. portion of the finely divided product which had been washed and dried as above was leached with benzene. The benzene solution was poured into methanol 40 to give, after washing and drying, 0.8 g. of polymer havng 1.66 wt. N (equal to 16.8 mole of C H NCO content) and an inherent viscosity 0.17 measured at 0.5% in chloroform at 25C.

EXAMPLE 44 Copolymer of Chloral, Butyl lsocyaanate, Phenyl lsocyanate and 2,4-Diisocyanatotoluene In a 300 ml., round-bottom, glass flask were placed 250 ml. of chloral, 13 ml. of butyl isocyanate, 13 ml. of phenyl isocyanate, 13 ml. of 2,4-diisocyanatotoluene, and 0.25 g. of Celanthrene red dye. The flask was equipped with a stand pipe which was closed with a calethoxycarbonylmethyl isocyanate;

3-cyano- 1 -methyl-'3 ,3 -diphenylprop yl isocyanate;

o-cyanophenyl isocyanate;

l-diethylaminol ,2,2-trifluoroethyl isocyanate;

a,a-dimethylphenethyl isocyanate;

heptafluoropropyl isocyanate;

2-iodol-indanyl isocyanate;

4-phenylanthryl isocyanate;

2,6-anthraquinonylene diisocyanate;

3-benzyloxy-4-methoxyphenethyl isocyanate;

trifluoromethyl isocyanate;

1 ,2,3 ,4 ,4a,9,10,lOa-octahydro-7-isopropyl-1,4a-

dimethyll -phenanthryl isocyanate;

2,4,6-triiodophenyl isocyanate;

abietyl isocyanate;

6-fluoro-2-pyridyl isocyanate;

l-adamantyl isocyanate;

3,3,3-trinitropropyl isocyanate;

2-(phenylthio)ethyl isocyanate;

p-phenylazophenyl isocyanate;

benzyl isothiocyanate;

butyl isocyanatoacetate;

p-bromophenyl isothiocyanate; p-butoxyphenyl isothiocyanate; o-chloro-a-phenylbenzyl isothiocyanate; 14-cyanotetradecyl isothiocyanate; cyclohexyl isothiocyanate; cyclooctyl isothiocyanate; 2-diethylaminoethyl isothiocyanate; 2,2-difluoroethyl isothiocyanate; 2,4-dinitrophenyl isothiocyanate; ethylene diisothiocyanate;

1 15 p-iodophenyl isothiocyanate; 4-methylthiobuty isothiocyanate; p-phenylene diisothiocyanate; 2-pyridyl isothiocyanate; p-(methylthio)phenyl isothiocyanate; and q-phenanthryl isothiocyanate.

EXAMPLE 45 Copolymer of Chloral and Diphenyl Ketene Part A In a dry test tube (18 X 200 mm.), which was blanketed with nitrogen, a mixture of 15 g. of freshly distilled chloral and l g. of freshly distilled diphenylketene was heated in an oil bath to 65C. A 1 molar solution of lithium tert-butoxide in cyclohexane (0.2 ml.) was then added and the mixture stirred, while still under nitrogen, to produce a uniform mixture. The threshold polymerization temperature of this mixture was 52C. One part of the calm, initiated mixture was left in the test EXAMPLE 46 Copolymer of Chloral and Butylethylketene EXAMPLES 47 and 48 Copolymerizations of chloral were carried out with dimethylketene and pentamethyleneketene using the procedure of Example 45 to produce films. These are tabulated in Table 11 together with Examples 45 and 46.

Table II Copolymerization of Chloral with Ketenes Molar I V Mech. Properties Feed Ratio Copolymer Mol Percent of Films Chloral Comonomer Chloral/ lnitiator* Analysis(%) Chloral in Tensile Ultimate Ex. (g.) Type Amount Ketene (ml.) C H Copolymer Str. Elong.

(p 45 15 diphenyl- 1.g. 20 0.2 19.15 0.91 967 6,3 20.5

ketene 19.18 0.92 46 30 butyl- 2 g. 12.5 0.4 16.82 0.82 99.0

ethylketene 47 30 dimethyl- 1.2 g. 12 0.4 17.23 1.14 98.0

ketene 48 30 penta- 0.8 g. 28 0.4 17.17 1.04 98.0

methylene' ketene Lithium ten-butoxide (1 molar) in cyclohexane.

EXAMPLE 49 tube, and the tube was placed without agitation into a C. bath. Polymerization in the unagitated mixture commenced almost immediately and was essentially complete in 1 hour. The tube containing the copolymer was taken out of the cooling bath and allowed to come to room temperature. The plug of chloral-diphenylketene copolymer was removed from the test tube.

Part B The other part of the initiated comonomer mixture was transferred under nitrogen at temperatures above 65C. to a mold formed by two glass plates separated by a strand of elastic fiber about 0.1 mm. thick. The assembly with its unagitated contents still under nitrogen was then placed in a bath at 40C. and maintained in placid condition for about one hour. A clear film of chloral-diphenylketene copolymer was obtained which was stiff and tough. The film was washed with carbon tetrachloride and dried. The polymer was insoluble in all common organic solvents. Elemental analysis for C and H (Table II) indicated that the polymer contained 3.3 mole percent of diphenylketene. The infrared spectrum showed a strong band at 5.75 t indicative of an ester linkage. The thermal stability of this sample was substantially improved over chloral homopolymer. The 5% weight loss temperature of the copolymer determined at a heating rate of 6C./min. in nitrogen was 235C. Typical samples of chloral homopolymer prepared by a similar process had 5% weight loss temperatures in the range of 85120C.

Copolymer of Chloral and Dimethylketene 'The supernatant air in the tube was evacuated after which the tube was sealed and heated to 60C. The tube was shaken vigorously to cause the steel balls to break the vial containing the initiator and to produce a homogeneous solution. After the contents of the tube had come to rest it was placed without agitation in a 30C. bath. Polymerization commenced in the-placid mixture almost immediately. The tube was taken out after an hour and the polymerization was allowed to go to completion overnight at room temperature. The initial yellow color of the solution almost completely disappeared during the polymerization. The tube was opened and a tough and stiff chloral-dimethylketene copolymer was obtained. Elemental analysis for carbon and hydrogen indicated the polymer contained 6% of dimethylketene, and the infrared spectrum of the polymer showed a strong ester band at 5.75 p.

EXAMPLES 50 and 51 Copolymerizations of chloral were carried out with ketene and methylketene using the sealed tube procedure'of Example 49. Details of these are known in Table III.

Table III Copolymerization of Chloral with Ketenes Molar Feed Ratio Copolymer Mol Percent Chloral Comonomer Chloral] lnitiator* Analysis(%) Chloral in Ex. (g.) Type Amount Ketene (ml.) C H Copolymer 49 3O dimethyl- 1.2 g. 12 0.4 17.17 1.15 98.0

ketene 17 .20 1.05 50 30 ketene 1.0 g. 8.5 0.4 16.95 0.88 95.2 51 3() methyl- 1.2 g. 9.5 0.4 16.92 1.05 96.1

ketene 16.91 1.08

*Lithium tert-butoxide (1 molar) in cyclohexane.

When the following ketenes are substituted for dimethylketene in the procedure of Example 49, the corresponding chloral-ketene copolymers are obtained:

phenoxyketene;

p-chlorophenoxyketene;

2,4-dichlorophenoxyketene;

2,4,6-trichlorophenoxyketene; diphenoxyketene;

bis(p-biphenylyl)ketene;

di-p-tolylketene;

dimesityketene;

dodecylethylketene;

durylphenylketene;

tetradecylketene;

octadecylketene;

benzylmethylketene;

cyclohexylketene;

dimethyleneketene (carbonylcyclopropane);

tetramethyleneketene (carbonylcyclopentane);

( l-naphthy1)phenylketene;

3,3,3-trichloropropylketene;

p-methoxyphenylketene;

dicyanoketene (carbonylmalononitrile);

(ethoxycarbonyhketene;

and (ethoxycarbonyl)-p-tolylketene.

FILLED COMPOSITIONS It has been pointed out above that the copolymers of this invention can be combined with fillers and reinforcing of all types whether inorganic or organic.

The chloral copolymer moiety of the filled compositions forms a matrix representing l99% by weight, of the total weight of the filled compositions and preferably 60-95% of the total weight of the filled compositions. When fiber fillers are used, such as especially treated glass fibers capable of chemical bond formation between the copolymer and glass fiber, tough rigid reinforced objects can be obtained. The filled chloral copolymer compositions, in general, possess a combinataion of mechanical and physical properties as follows:

' good weathering, high rigidty, non-burning, as they do not support combustion, and good tensile and impact strength. When a bond is formed between the matrix resin and the filler, an added property of good hydrolytic stability is obtained. Preferably, this bond should be a chemical bond such as that formed between the copolymer and glass treated with a vinyl-silane or Werner-type chromatic complex containing an addition polymerizable group. However, good properties are observed in filled compositions where the bond between the matrix copolymer and filler is other than a chemical bond such as a Van der Waals bond.

Filled composition are prepared by mixing fillers with a catalyzed mixture of chloral and comonomers prior to cryotachensic polymerization. Alternatively, the

filler can be mixed with the mixture of monomers, then after complete mixing, the desired quantity of initiator is added to the mixture, prior to cryotachensic polymerization. It is preferable to degas the catalyzed mixtures prior to polymerization to remove oxygen and any other dissolved gas present to minimize the formation of voids in the final product.

Rigid shaped objects can be produced with the catalyzed filler-monomer mixture such as flat, curved, corrugated or otherwise shaped sheets for glazing and architectural uses, automobile bodies, exterior step treads, boat hulls and decking, fishing poles, fire barriers, laundry tubs, electrical appliance housings, bearings, motor insulation, rocket motor casings and the like. The non-burning characteristics of the products of this invention make them particularly advantageous in these uses.

The mechanical properties of the reinforced copolymer panels compare very favorably with the mechanical properties of available fiber glass reinforced polyester compositions.

The chloral copolymer reinforced sheets are completely noncombustible whereas polyester panels burn vigorously and even so called flame retardant compositions support combustion when compared in the American Society for Testing and Materials (ASTM) flammability test D635-63.

EXAMPLE 52 Copolymer of Chloral and p-Phenyl Isocyanate Filled with Glass Wool A layer of glass wood about 3 mm. thick, measuring about 220 mm. X mm. and weighing about 15 g. was placed between two 3 mm. glass plates measuring mm. X 280 mm. A length of 6 mm. X 1.5mm. wall gurn rubber tubing was inserted between the plates about 1 inch in from the edges to serve as a gasket which was liquid tight except for a smell opening near one comer through which the polymerizable monomer mixture can be introduced. The assembly was clamped together with spring clamps on all edges and heated to 60C. A mixture of chloral (93.5 ml.) and p-chlorophenyl isocyanate (6.2 ml.) was. heated under nitrogen to 68C. and mixed with 4.0 ml. of a 1 molar solution of triphenyl phosphine in benzene. This initiated monomer mixture was transferred. with a preheated (60C.) hypodermic syringe having a large bore (12 ga) needle long enough to reach nearly to the bottom of the glassfilled mold. The preheated mold was'carefully filled, from the bottom up in order to displace the air trapped in the glass, with the hot mixture of initiated monomer. With the polymerization mixture in quiescent condition, the filled mold was quickly immersed in ice water taking care to keep any water from getting into the casting through the opening in the gasket and to keep 19 the polymerization mixture quiescent during the polymerization. After one hour the mold was removed from the ice bath and allowed to warm to room temperature overnight. One half (A) of the strong, hard, nearly transparent reinforced chloral/p-chlorophenyl isocyanate copolymer sheet was curedin a 100C. air over. After 24 hours it had lost 22.2% in weight, but was essentially unchanged in length or width. The other half 20 (B) of the sheet was allowed to air dry. It lost less than 3% in weight in one week.

Examples 53-80 which follow, show the preparation of chloral homopolymer and copolymer sheets reinforced with selected fibrous materials and prepared in the manner indicated. The detailed procedure of Example 52 was used except for the differences shown.

TABLE IV Fibrous Monomer Charge Reinforcing Agent Tensile Chloral Comonomer Initiator Strength Elongation Example Material g. ml ml ml Work-up Procedure (pal) 1 53 Glass wool 26.2 93.5 6.2A 4.013 Under vacuum for 5,930

(as in Ex. 52) 2 days 54 Polypivalolactone 93.5 6.2A 403 Air dry 100C., 168 hrs. 55 Polyethylene 4.5 93.5 6.2A 4.0B Air dry 3,730 24.0

terephthalate 56 Polypropylene 12.0 93.5 6.2A 4.0B Air dry 57 Fiber glass 35.0 93.5 6.2A 408 Air dry 12,5 80 2.5

100C., 169 hrs. 58 Fiber glass 35.0 93.5 6.2A 4.0B Air dry 11,500 3.2 100C., 169 hrs. 12,720 2.5 59 Fiber glass 27.3 140.3 10.5C 6.0B 120C., 1 hr. 13,800 2.0 60 Fiber glass 28.2 140.3 9.3A 6.013 120C., 1 hr. 5,900 2 61 Fiber glass 8.3 140.3 9.3A 6.0B 120C., 1 hr. 6,190 62 Fiber glass 20.6 140.3 9.3A 6.0B 120C., 1 hr. 9,560 Fiber glass 50.0 140.3 9.3A 608 120C., 1 hr. 12,800 64 Fiber glass 39.4 140.3 9.3A 6.0B 120C., 1 hr. 11,300 65 Fiber glass 51.6 140.3 9.3A 608 120C., 1 hr. 16,600 66 Fiber glass 26.8 140 8.25D 603 120C., 1 hr. 8,880 67 Fiber glass 26.7 140 10.5E 6.0B 120C., 1 hr. 5,410 68 Fiber glass 28.5 140 10.5F 6.0B 120C., 1 hr. 9,810 69 Fiber glass 27.4 140 12.00 6.0B 120C., 1 hr. 11,100 70 Fiber glass 25.9 140' 14.25H 6.0B 120C., 1 hr. 10,600 71 Fiber glass 1 27.7 140 9.11 6.013 120C., 1 hr. 5,350 72 Fiber glass 28.4 140 I None 6.0B 120C., 1 hr. 7,190 73 Fiber glass 28.3 144 4.6F 6.013 120C., 1 hr. 9,930 74 Fiber glass 26.2 135 24.0F 608 120C., 1 hr. 7,310 75 Fiber glass 27.0 147 1.8A 6.013 120C., 1 hr. 11,100, 3.3 76 Fiber glass 26.6 143 5.6A 6.0B 120C., 1 hr. 8,990 3.1 77 Fiber glass 26.6 140 11.0A 6.0B 120C., 1 hr. 11,000 3.8 78 Fiber glass 25.2 137 16.5A 6.0B 120C., 1 hr. 7,660 2.6 79 Fiber glass 26.6 130 24.0A 608 120C., 1 hr. 4,580 2.7 80 Fiber glass 27.8 126 30.0A 608 C., 1 hr. 8,570 3.4

Notched Flexural Flexural Izod Impact Modulus Strength Strength Example (psi) (psi) (ft lbs/in Reports 53 229,000 1.58 Strong, hard sheet of reinforced chloral/pchlorophenyl isocyanate copolymer 54 3.82 Strong, hard reinforced copolymer sheet 3.94 Strong, hard reinforcedcopolymer sheet 55 1.34 Strong, hard reinforced copolymer sheet 56 4.84 Strong, hard reinforced copolymer sheet 57 12.2 Strong, hard reinforced copolymer sheet 571,000 16,600 1 1.7 Strong, hard reinforced copolymer sheet 58 453,000 12,800 12.9 Strong, hard reinforced copolymer sheet 14.8 Strong, hard reinforced copolymer sheet 59 576,000 20,000 11.7 Strong, hard sheet of reinforced chloral/2,4-

toluene diisocyanate copolymer 60 300,000 10,000 17.7 Strong, hard reinforced copolymer sheet 61 362,000 9,940 9.4 8.3 vol. glass 62 464,000 14,200 7.9 10.6 vol. glass 63 593,000 16,200 10.4 14.7 v01. glass 64 539,000 14,100 13.5 24.3 vol. glass 65 752,000 19,700 16.2 45.2 vol. glass 66 574,000 16,400 9.2 Strong, hard sheet of reinforced chloral/phenyl isocyanate copolymer 67 718,000 15,000 14.5 Strong, hard sheet of reinforced chloral/diphenyl ketene copolymer 60 595,000 18,900 1 1.8 Strong, hard sheet of reinforced chloral/toluene diisocyanate copolymer. 5 mole toluene diisocyanate 69 14.6 Strong, hard sheet of reinforced chloral/ hexamethylene diisocyanate copolymer 70 643,000 18,200 9.8 Strong, hard sheet of reinforced chloral/ p-p-diisocyanatediphenylmethane copolymer 71 532,000 13,100 1 1.2 Strong, hard sheet of reinforced chloral/2,5

dichlorophenyl isocyanate copolymer 72 652,000 15,900 9.9 Strong hard sheet of reinforced polychloral 73 476,000 12,000 10.4 2 Mole percent toluene diisocyanate 74 539,000 10,400 1 1.1 10 Mole percent toluene diiocyanate 75 487,000 13,500 10.6 1 Mole percent p-chlorophenyl isocyanate 76 470,000 13,100 9.9 3 Mole percent p-chlorophenyl isocyanate 77 517,000 15,200 10.5 6 Mole percent p-chlorophenyl isocyanate 78 487,000 14,600 13.2 8 Mole percent p-chlorophenyl isocyanate 79 394,000 12,900 10.8 12 Mole percent p-chlorophenyl isocyanate TABLE IV-continued Notched Flexural Flexural Izod Impact Modulus Strength Strength Example (psi) (psi) (ft lbs/in Reports 80 385,000 1 1 ,200 12.9 Mole percent p-chlorophenyl isocyanate Bat of fibers having strengths of 1.5 grams per denier. prepared from polypiralolactone fibers of US. patent 2,658,055

Random fibers in bat form Chopped glass fiber reinforcing bat treated with a silane.

Washed with chloroform and vacuum dried before use. Washed with acetone and dried before use. Continuous fiber reinforcing bat treated with a silane. Washed with chloroform and .dried before use.

EXAMPLE 81 A. Fabric-Reinforced Pipe of Chloral Polymers The bottom third of each of a series of 18 mm. outside diameter (OD) test tubes was wrapped with 50 mm. wide strips of various fabrics until the wrapped test tube would just comfortably fit inside a test tube of 26 mm. inside diameter (ID). The coaxially assembled tubes were held under vacuum at 70C. to remove any traces of moisture and the free space between the heated test tubes was filled with chloral monomer heated to 68C. to which had been added 0.1 mole percent of lithium tert-butoxide. The polymerization mixtures were allowed to become placid and the filled assemblies were then chilled to 0C. for periods of time ranging from 20 min. to 16 hours without agitating the polymerization mixtures. After the assemblies had warmed to room temperature, the test tubes were broken away to leave short lengths of fabric reinforced cylinders of strong, hard polychloral about 2 inches long, 18 mm. ID, and 26 mm. OD. Cylinders reinforced with woven fiberglass cloth, woven polytetrafluoroethylene fabric, fiberglass filter cloth, and nonwoven felts of polypivalolactone and polypropylene were prepared. Similarly strong reinforced tubes of chloral copolymers are obtained when the chloral/-p-chlorophenyl isocyanate/triphenylphosphine mixture of Example 52 is used in place of the chloral/lithium tert-butoxide mixture above.

B. Non-Reinforced Pipe of Chloral-Phenyl Isocyanate Copolymers.

An open-ended glass tube about 300 mm. long and 75 mm. inside diameter was fitted with a rubber stopper at each end, each stopper having a central opening.

A second, smaller glass tube about 300 mm. long but with an outside diameter of 45 mm. was positioned coaxially within the larger tube by insertion through the central openings in the rubber stoppers, and the assembly mounted vertically. The small inner tube was closed at its bottom end with a solid rubber stopper. The upper stopper of the outer tube was additionally provided with two smaller holes opening into the bore of the outer tube, one to admit nitrogen gas and the other, itself loosely stoppered, to admit monomer and initiator into the bore of the outer tube. Hot (65C.) water was circulated through the smaller tube and a 65C. water bath raised around the outer one. A mixture of chloral (625 ml.) and phenyl isocyanate (29 ml., 4 mole was heated to 65C., mixed with 33 ml. of 3.2% lithium tertbutoxide in cyclohexane and used to A. p-chlorophenyl isocyanate B. l-Molar triphenylphosphine in benzene C. 2,4-Toluene diiso cyanate D. Phenyl isocyanate E. Diphenyl ketene F. 2,4-Toleune diisocyanate, 20% 2,6-toluene diisocyanate G. Hexamethylene diisocyanate H. p p-Diisocyanatediphenylmethane l. 2,5-Dicl1lorophenyl isocyanate fill the annular space between the concentric tubes and the resulting homogeneous mixture allowed to become motionless. Circulation of the hot water in the inner tube was continued but the hot water bath surrounding the outer tube was removed. A 20C. cooling bath was then raised around the outer tube at the rate of 3 mm.per minute until the cooling bath reached the top level of the quiescent polymerization mixture and completely surrounded it. Cooling of the outer tube was continued for 30 minutes while the inner tube was still being kept warm. After 30 minutes of standing under these conditions, the flow of hot water into the inner tube was stopped and the hot water in the tube was removed by suction, the cooling bath still being in position around the outer tube. After another 30 minute period the stopper closing the bottom end of the inner tube was removed thus allowing the -20C. bath liquid to enter and fill the center tube. After 30 minutes of thus cooling both the inside and outside tubes, the cold bath was removed and the resulting copolymer product allowed towarm to room temperature overnight before the glass was broken away. The resulting pipe section was void-free and had a smooth, outer surface. The inner surface was relatively rough and uneven. Since the manner of cooling caused polymerization to occur from the outer wall inward, the shrinkage which occurred during polymerization caused the polymer to shrink away from the inner tub-e. The inner surface was machined smooth to give a strong pipe about 200 mm. long 75 mm. OD, and 50 mm. ID.

EXAMPLE 82 Chloral, p-Chlorophenyl Isocyante, Diphenylketene Terpolymer In a dry 250 ml. glass flask which was continuously blanketed Wth nitrogen, there was mixed ml. of freshly distilled chloral, 9.3 ml. of p-chlorophenyl isoa cyanate and 1.5 ml. of diphenylketene. The mixture was heated to 65C. and 6.0 ml. of a 1 molar solution of triphenylphosphine in benzene: was added and mixed in well to form a uniform mixture. The initiator-containing mixture was transferred at temperatures above 60C. to a mold formed of two glass plates separated by a 3 mm. gum-rubber gasket and the mixture allowed to become motionless. The assembly was cooled at 0C. to bring about polymerization of the motionless mixture. The mold was opened after polymerization had been completed to release a clear, tough 3 mm. thick sheet of chloral/p-chlorophenyl -isocyanate/-diphenylketene terpolymer useful for glazing.

liXAMPLl'l s3 l1. Chloral.p-(hlorophenyl lsocyanate. llexyl lsocyauate 'l'erpolymer The procedure of l'lxamplc 82 was repeated using a mixture of I40 ml. chloral. 7 ml. pchlorophenyl isocyanate. 2 ml. hexyl isocyanatc and 6.0 ml. of l molar solution oftriphenylphosphine in benzene. A tough. clear sheet ofchltvral/p-chlortvphenyl isocyanate/hesyl isocy anate terpolymer was obtained.

liXAMPLl. 84

Chloral. Diphenylketene. 3.4-Dibromophenyl lsocyanate. llexamethylene Diisocyanate 'l'etrapolymcr Part A In a dry 500-ml. lirlennteyer llask. which was blanketed with nitrogen. a mixture of 2l0 g. ('l.40 moles. 93,6 mole 70) of freshly distilled chloral. 9.2 g. (0.05 mole. 3.l mole 70) of diphenyl ketene. 8.3 g. (0.03 mole. 2.0 mole '71-) of 3.4-dibromophenyl isoeyanate and 3.3 g. (0.02 mole. l.3 mole '74) of hexamethylene q dusocyanate was heated to 55( A l-molar solution of triphenyl phosphine in benzene (6.0 ml.)"was then added and mixed in well to form a homogeneous solution. One part of this heated mixture was transferred into a warm test tube. and the tube was then cooled to 0C. without agitation. Polymerization commenced almost immediately and was essentially completed in one hour to form a tetrapolymer. The tube containing the tetrapolymer was then allowed to come to room temperature. The plug of chloral/diphcnyl ketene/JA- dibromophenyl isocyanate/hexamethylene diisoeya nate tetrapolymer was then removed from the test tube. extracted for 50 hours with acetone. dried for 20 hours at 60C./l mln. and analyzed: C. l).4l; H. l.00; N. 0.27; Br. 2.75; and Cl. 66.66. This corresponds to a ehloral/diphenyl ketene/3.4-dibromophenyl isocyanate/hexamethylenc diisocyanate molar ratio of )5/l.5/2.5/l .0 for which the calculated analysis is C. I873; H. 0.83. N. 0.4l; Br. 2.60; Cl. 66.67.

Part I) Another part of the above heated initiated mixture of monomers as prepared in Part A was transferred at temperatures above 55C. to a mold formed by two glass plates separated by a strand of elastic fiber about 0.] mm. thick. The assembly and its quiescent contents was then cooled to 0C. without agitation and kept at that temperature for about one hour. A clear llim of Part C Another part ofthe above described. heated initiated mixture of monomers as prepared in Part A was transferred at temperature above 55C. to a mold formed by two glass plates separated by rubber tubing to make 3 mm. thick sheets. The assembly and its quiescent contents was then cooled to 0C. without agitation and kept at that temperature for about one hour. A clear sheet of cltloral/diphenyl ketene/3.4-dibromophenyl isticyanate/hexamethylene diisocyanate was obtained which was stiffand tough. It was extracted with acetone as described in Part A. Elemental analysis for C. H. N. and Br. (C. I); H. 0.98. N. 0.26; Br 2.2) CI. 67.21) indicated the chloral polymer contained )5 mole percent of chloral. l.5 mole percent of diphenyl ketene. 2.5 mole percent of3.4-dibromophenyl isocyanate. and I0 mole percent of hexamethylene diisocyanate. The infrared spectrum (Nujol mull) showed a strong band at 5.70; indicative of a urethane linkage. and a weaker. well separated band at 5.85 1. indicative of an ester linkage.

liXAMPLli Chloral-Phenyl lsocyanate Copolymer Filled With Carbon Black An initated monomer solution was prepared by mixing 30 ml. of chloral. I50 ml. of toluene and 0. l 2 g. of lithium tert-butoxide at 30C. To 25 mol. of this solution in a I25 ml. Erlcnmyer flask closed with a rubber stopper was added 0.2 g. of carbon black. The flask was shaken quickly to disperse the carbon black and when uniform and quiescent. the mixture was placed in an ice bath and held until the chloral monomer gelled. Polymerization was completed by cooling to 5C. for l2 hours. Residual solvent was removed at 0.2 mm. pressure. The polymer plug obtained was soaked with a 20% phenylisoeyanate solution in toluene for a time sufficient to allow formation of a eopolymer of chloral and phenylisoeyanate. The sample was washed and driedto give a shiny black block of polymer which was machined into a flat chip about 4 mm. thick and 33 mm. in diameter.

EXAMPLE 86 A. Chloral. p-Chlorophenyl lsocyanate Copolymer With Phthalocyanine Blue Pigment An experiment similar to Example 85 was carried out with copper phthalocyanine blue (0.025 g.) was dispersed in the above initiated chloral mixture (40 ml.) and polymerization was carried out as described above to give a eopolymer plug having a deep blue color.

l3. Chloral. p-Chlorophenyl lsocyanate (opolymer With Poly l'ctrafluorothylene Flock as Filler An experiment similar to Example 85 was carried out with fluorocarbon polymer llock instead of carbon black. 10 grams of chopped fibers of polytetratluoroethylene were suspended in 60 ml. of the above initiated chloral mixture and polymerization carried out as described above under lixample 85. A flock tilled co polymer was obtained.

EXAMPLE S7 Pigmented Chloral. p-Chlorophenyl lsoeyanate Copolymers .lo a mixture of l0 ml. of chloral and 0.6 ml. of pehlorophenylisocyanate was added at 60C. a one molar benzene solution of triphenylphosphine (0.4 ml.) and 0.025 g. or 0.050 g. of the following pigments in separate experiments: Polychloro copper phthalocyanine, copper phthalocyanine blue, beta quinacridone, gamma quinacridone, coat d lead chromate pigment, (U.S. Pat. No. 2,885,366), coated molybdate orange pigment (U.S. 2,885,336), and nickel azo complex.

The uniform, quiescent mixtures were placed in an ice bath for 2 hours and then allowed to stand for 16 hours at room temperature. The polymerization was accomplished smoothly and gave polymer pieces which lost approximately 10% weight upon heating for 1 hour at 120C. The pieces did not change color during the heat treatment.

EXAMPLE 88 Chloral, p-Chlorophenyl lsocyanate Copol'ymer Filled With Titanium Dioxide To a mixture of Chloral (140 ml.) and p-chlorophenylisocyanate (9.3 ml.), at 50 was added a one molar benzene solution of triphenylphosphine (6 ml.) and finely divided TiO (4 g.). This mixture was placed between glass plates held apart with a3 mm. rubber spacer.

The assembly and its quiescent contents was placed in an ice bath for 1 hour and then held for 16 hours at room temperature for completion of the polymerization. The pigmented polymer sheet was heat treated for 1 hour at 120C. The weight loss was 19% to give a white, opaque sheet.

For each of the following dyed copolymer preparations listed in Table V, the following polymerization mixture was used: chloral (70 ml.), p-chlorophenylisocyanate (4.2 ml.) and a one molar benzene solution of triphenylphosphine (2.8 ml.). To the mixture heated at 50C., a dye (type and amount as shown in Table V) was added, and the homogeneous solution was placed in a cell formed formed by glass plates held apart by a 3 mm. polyvinyl chloride spacer. Polymerization was carried out by placing the assembly and its motionless polymerization mixture in an-ice bath at C. for 2 hours, and then held at room temperature for 16 hours. Colored copolymer sheets having a thickness 1 of 3 mm. and good color stability, even after' heat treatment for 1 hour at 120C. (weight loss 8-1 4%), were TABLE Y-continued Amt. Ex. Dye (8-) NH CH 92 0.2 O N- Q N=N NCH,CH CN fit 94 C 0 15 The unpolymerized liquid mixtures of chloral and the comonomers described above and these liquids containing a polymerization catalyst, aprotic solvent or filler from another embodiment of the invention. The concentration of chloral, comonomers, catalysts, aprotic solvents, fillers, etc., are as described above. The liquid mixtures of chloral and comonomers without initiator can conveniently be stored and shipped prior to polymerization since they do not undergo polymerization in the absence of a polymerization initiator. The unpolymerized liquid mixtures containing a catalyst may be stored and shipped if they are maintained above the threshold polymerization temperature of the particular liquid. It should be understood, however, that storage times may vary from one composition to another, some being storable and shippable for longer periods of time than,others. These liquid mixtures can be heated in a range whose lower limit is above their threshold temperature and whose upper limit is below their reflux temperature. However the temperature should not exceed the decomposition temperature of any of the ingredients of said liquid mixtures. Fillers can be added to the mixture of monomers maintained above the threshold temperature. The filler-comonomer mixtures are in the form of a paste having a v dough-like consistency which can be fabricated into shaped objects by matched-die molding coupled with cooling the mixture below the threshold temperature.

The conversion of comonomers to polymer may be made over wide ranges of polymerization conditions.

EXAMPLE 96 Conversion Ex. No. Polymerization conditions (1) (2) A 1 hr. at 35C., 16 hrs. at *r.t. 77.4 57.3 B 1 hr. at C., 16 hrs at r.t. 88.5 69.8 C 5 min. at 0C., 16 hrs. at r.t. 86.6 69.4 D 16 hrs. at 0C. 89.6 73.8 E 1 hr. at 0C. 85.8 66.8 F 1 hr. at 50C., 16 hrs. at r.t. 82.3 60.6

*room temperature STABILIZATION OF POLYMERS BY HEAT TREATMENT It has been mentioned earlier that solvent and unpolymerized monomers may be removed from the copolymers of this invention by evaporation or extraction. Such treatment results in polymer of enhanced thermal stability.

. The polymers may also be stabilized against thermal degradation by, surprisingly enough, a heat treatment at a temperature range of 80 to 175C. for a period of time ranging from 5 minutes up to several hours. It is believed that the raw polymers contain stable polymer, an unstable fraction, and unchanged monomers and solvent. In order to prepare polymers having enhanced usefulness, particularly for extended use at elevated temperatures, the solvent and unchanged monomers should be removed and more importantly the less stable portion present in the polymer should be altered or removed. The heat treatment appears to remove the solvent and unchanged monomers and also results in an enhancement of the thermal stability of the polymer.

This is a most surprising phenomenon since other raw polymers, not previously treated for heat stability, such as polyvinyl chloride and polyoxymethylene decompose autocatalytically when heated and become less stable rather than more stable to heat. Samples of the copolymers of this invention that lost weight rapidly at first, 6% in the first 100 hours at 100C, became essentially' weight-stable, 6511 0.7% loss per week, after being heated at 100C. r 600 hours.

EXAMPLE 97 ,A. Copo1ymer of Chloral and p-Chlorophenyl 'lsocyanate A clear sheet 3mm. thick of 95/5 mole ratio chloral/p-chlorophenyl isocyanate, prepared according to Example 52 but omitting the glass wool, was cut into four pieces. Piece I was not treated further. Pieces 11, 111, and IV were baked in a 120C. air oven for l 2 and 6 hrs., respectively. The relative thermal stability of the four pieces at 60 was then determined by measuring the further loss in weight after 225 hrs. at'60f. I lost 18.8% while 11, 111 and IV lost only 1.5, 0.3 and 01% respectively.

B. Copolymer of Chloral and Toluene Diisocyanate A sheet like that in A was made substituting toluen e diisocyanate for the p-chlorophenyl isocyanate to give a 95/5 mole ratio copolymer of chloral/toluene diisocyanate. The sheet was cut into four'pieces. Piece 1 was not further treated. Pieces 11, llland lV-were baked at i 120C. for 1, 2 and 6 hours, respectively as-fin A. On aging at 60C. for 225 hrs. 1 lost 146% while 11,111, and IV lost only 0.2, 0.2 and 0.0%, respectively. .2.

STABILIZATION OF POLYMERS B WEN EXTRACTION The copolymers resulting from the cryotacherisic'copolymerization process can be processed in various ways in order to remove any last traces of unpolymerized monomers. For some purposes it is sufficient merely to allow the polymerized piece to air dry wheneupon the unpolymerized material spontaneously evaporates; This is illustrated for example in Examples i4,l and 42. The unchanged monomers are removedsomewhat more rapidly by holding the polymerizedpiece under reduced pressurefor a period as in Examples .2

or 53. Even more effective in removal of unchanged 'monomers as well as initiator residues in the process; of

washing'or exhaustively extractingthe polymer: witha liquid in which the monomers are-soluble butthepolymer insoluble. 1n the case of those polymers of -the present application which contain atleast-aboutr80' mol percent chloral, the choice of solvent for suchan extractive procedure is quite'wide since the monomers empolyed are generally soluble in organic liquidswhile the polymers are not. Unchanged chloral can be removed from the polymer with water. Such extractive procedures are illustrated in Examples 2 and 45 B.

Washing or exhaustive extraction of the copolymers of the present application with liquid is as stated above very effective in removal of unchanged monomer but in addition washing or exhaustive extraction with certain selective solvents results in products of enhanced thermal stability and resistance to discoloration on expo- 29 example which give polymer of enhanced thermal stability, do in fact bring about weight losses much greater than other solvents such as water or carbon tetrachloride, which do not markedly enhance thermal stability.

EXAMPLE 98 Copolymer of Chloral and p-Chlorophenyl Isocyanate Transparent clear sheets 3 mm. thick were prepared by the general procedure of Example 52 but no glass wool was used between the plates. The monomer mixture consisted of 140 ml. of chloral and 9.3 ml. of pchlorophenyl isocyanate. It was heated to 52C. and 6.0 ml. of a l-molar solution of triphenyl phosphine in benzene was added. The polymerization was effected by cooling the uniform, quiescent polymerization mixture at C. for l hour. After standing overnight the resultant sheets were baked for 1 hour at 120C. and lost about 12% in weight to give clear transparent panels essentially free of unpolymerized chloral. The sheets were cut into strips 12.5 mm. wide and about 6 inches long. Each piece was weighed, placed in about 50 ml.

of solvent, allowed to stand at room temperature or at 60C. for 8 hrs., dried in vacuo at 50C. andreweighed. This extraction procedure was repeated with fresh solvent each time for eight cycles until the weight loss, ex

- pressed as percent of the original weight, was constant.

As a measure of thermal stability the percent of weight loss on holding the extracted piece in a circulating air oven at 200C. was then measured.

Thermal Ex. Extraction lost on Stability lost No. Extractant Temp. Extraction in 4 hrs. at 200 A None 34.2 B Water r.t. 2.0 27.1 60C. 2.4 35.2 C CCl. r.t. 2.5 20.5 60C. 2.7 21.8 D CllCl r.t. 12.4 3.9 60C. 12.5 3.3 E Benzene r.t. 14.1 7.3 60C. 15.3 3.5 F Pentane r.t. 14.3 I 1.7 G Z-butanone r.t. 18 .4 3.1 60C. 18.6 2.0 i H CH,C1 r.t. 17.9 1.0 I Acetone r.t. 18.5 4.6 60C. 19.3 1.5

room temperature STABILIZATION OF POLYMERS WITH ULTRAVIOLET LIGHT SCREENING AGENTS the polymers of the invention can be protected against discoloration by ultraviolet irradiation by the incorporation of ultra violet screening agents. These agents can be incorporated after the polymerization is effected.

30 process hasbeen carried out or by adding the agent directly into the monomermixture before polymerization Incorporation of such screening agents or light stabilizerslinto the formed polymercan be accomplished by soaking the polymer in the light stabilizer or a 0.120% solution thereof in an organic solvent.

EXAMPLE 99 Copolymer of Chloral and p-Chlorophenyl Isocyanate EXAMPLE 100 Copolymer of Chloral and p-Chlorophenyl Isocyanate A clear sheet 3 mm. thick of 95/5 mole ratio chloral/p-chlorophenyl isocyanate copolymer like that of Example 52 was baked 1 hr. at C. and cut into strips 1/2 inch wide and 5 inches long. Three pieces were soaked in a 2% solution of (a) 2( 2-hydroxy-3 ,5 ditertbutylphenyl)benzotriazole available from Geigy Chem. Corp. of Ardsley, New York, as Tinuvin 327,

(b) ethyl 2-cyano-3,3-diphenyl acrylate available from General Aniline and Film Corp., New York, NY. as Uvinul N-35 and (c) 2,2'-dihydroxy-4,4-dimethoxy benzophenone also available from General Aniline and Film Corp as Uvinul D-49. A fourth piece (d) was left untreated. On outdoor exposure (d) turned quite dark while (a), (b) and (c) remained nearly colorless.

In addition to the specific be nzophenone, benzotriazole and substituted. acrylate type ultra violet screens. shown above, other'members of these three types may be used. Examples which might be mentioned are 2- hydroxy-4-methloxy 'benzophenone, 2-(2'-hydroxy-5- methylphenyl) benzotrizole and 2-hydroxy-4-(2- hydroxy-3-methylacryloxy)propoxybenzophenone. Other types of light. stabilizers are listed in Modern Plastics Encyc. and: include methyl salicylate, phenyl salicylate and resorcinol monobenzoate.

IMPROVED CONVERSION OF MONOMER TO POLYMER The use of an aprotic liquid has been disclosed above as an acid indispersing or dissolving the initiator in the chloral. Often the liquidis additionally useful in providing enough shrinkage of the polymerized piece to permit its ready removal from the mold in which the polymerization process was carried out.

It has been furthe found that the use of certain aprotic liquids enhance the conversion of the comonomers to the copolymers, an effect which has also been observed in the homopolymerization of chloral. I-Iigh conversion of stable polychloral and chloral copolymers is attained by carrying out the copolymerization in the presence of up to 95 vol. percent of an inert aprotic diluent. These inert diluents are hydrocarbons such as pentane, hexane, cyclohexane, heptane, Nujol (liquid paraffinic hydrocarbons), toluene, xylene, etc; halocarbons such as carbon tetrachloride, trichloroethylene, tetrachloroethylene, 1 ,1 l-trifluorododecane,

trichlorotrifluoroethane, chlorinated biphenyls (Aro --EXAMP13E 1- Chloral, p-Chlorophenyl lsocyanate Copolymer Chloral/p-chlorophenyl isocyanate monomer mixture, 95/5 mole ratio 10 ml), was diluted with 2 ml. of the solvent indicated and heated to 48C. a temperature which is in excess of the threshold temperature. Initiator (0.4 ml. of 1 molar triphenylphosphine in benzene) was added. The resulting homogeneous mixture was allowed to become quiescent, cooled without agitation to 0C. and held at that temperature for 1.5 hours. After standing overnight at room temperature, the polymerized plugs were weighed, baked 1 hour at 120C. to remove the diluent and the unchanged monomer, reweighed and the conversion of monomer to polymer (treated at 120C.) calculated. Without the diluent present the conversion of monomer'to polymer was 87-89%. The presence of vol. of diluent, based on chloral, enhancer the conversion of polymer up to as much as 97%.

No. Diluent vol. wt. Q conversion A benzene 20 10.6 94.8 B cyclohexane 20 9.4 97.1 C diethyl ether 20 8.6 93.8 D pentane 20 7.6 94.3

EXAMPLE 102 .Chloral, p-Chlorophenyl lsocyanate Copolymer As shown in Examples 101 and 102 above, copolymers form in higher conversions from monomer'mixtures containing volatile diluents as compared with undiluted monomers. The same is true for monomer mixtures diluted with such nonvolatile diluents as Nujol or Aroclorj Copolymers containing such nonvolatile diluents can be isolated by baking out the unchanged chloral, to leave homogeneous solids still containing the nonvolatile diluent uniformly dispersed in the chloral copolymer. Byextraction with a suitable solvent such as acetone the nonvolatile diluent as well as the unchanged monomer can be removed to leave unmodified copolymer free of the diluent. In either case, conversion of monomers to copolymer is enhanced over 15 the conversion realized in the absence of diluent.

EXAMPLE 103 A. Copolymers of Chloral and p-Chlorophenyl lsocyanate A homogeneouos mixture of 10 ml. ofv chloral, 0.6 ml. of p-chlorophenyl isocyanate and 0.4 ml. of a 1- molar solution of triphenylphosphine in benzene was prepared in a test tube at C. The tube and its placid contents was cooled without shaking to 0C. for 1.5 hours, held at room temperature for 16 hours, and then the resulting polymer plug was baked forl hour at C. The conversion to polymer was 92.3% Similar plugs to which 5 and 10% by weight of Nujol (light mineral oil) or 5 and 10% by weight of Aroclorv (mixture of chlorinated biphenyls) had been added to the monomer mixture before polymerization was effected gave conversions to polymer of 94.9, 94.9, 93.0, and 95.7%, respectively. These plugs were homogeneous mixtures of copolymer with non-volatile diluent. The conversions of comonomers jto copolymer were calculated from the known weights of ingredients employed and the observed weight of unchanged monomer lost on baking.

B. Copolymers of Chloral and pChlorophenyl lsocyanate In the following examples 3 mm. sheets were extracted with acetone to remove not only the unchanged monomer but also the nonvolatile diluent. The enhancement of conversion by virtue of the presents of diluent during polymerization is shown.

Diluent wt. diluent Percent conversion No. (ml. added) in mixture of comonomers to polymer after 4 hrs. at 120C 1 hr. at 120 followed by acetone extraction A None 1.8 84.0

B cyclohexane (51) 21.8 97.7

C benzene (45) 21.8 96.7

D hexane (12.5) 6.8 91.6

E hexane (21.0) 9.7 91.9

F hexane (32.5) 13.8 96.3 G hexane (42.4) 16.8 97.0

H hexane (60.0) 21.8 97.7

1 ether (25) 11.1 96.6

J None 1.8 75.0

K tetrachloroethylene (47.0) 34.0 88.9 L carbon tetrachloride (47.0) 33.5 86.5 M toluene (47.0) 22.2 88.6 N CCI FCF CI (47.0) 32.6 82.0

Wt. 7: total diluent including the 1.8% from the benzene of the initiator solution. 7

polymerization. After standing overnight at room temperature each sheet was weighed, extracted with acetone for 24-hrs.', dried in vacuo at 60C., r'eweighed and the conversion of monomer to polymer calculated.

Diluent (g) Ex. No. Total wt. diluent. Conversion T none 1.4 76.4 11 Nujol (25) 11.1 84.6 111 Nujol (12.5) 6.4 81.3

lV Aroclor (25) 11.1 80.9

The total weight percent of diluent in the charge includes not only the added Nujol or Aroclor but also the benzene introduced as solvent for the initiator.

FOAMED POLYMERS A prior example, No. 42, shows the formation of a foamed chloral copolymer using pentane as a solvent for the monomers. Certain fluorocarbons exhibit 'the same property and since chloral copolymers do not support combustion nor melt, non-drip, non-flammable foams of these polymers are highly useful in various applications such as the building materials industry.

The foamed products are obtained by dilution of the monomers before polymerization with from about 30 to 80 vol. percent of Freon 112 a, 1,1-difluorotetrachloroethane (CCl CClF Freon 3F, 1,2-difluorotetrachloroethane (CCl FCCl F), and Freon 111, monofluoropentachloroethane (C Cl F). These compounds are relatively high-melting compounds, melting at 40, 26. and 100C., respectively. They boilat 9 l.5, 92, and 137C., respectively. The monomer-Freon solution is cooled to effect polymerization and thenthe Freon is removed in vacuo at room temperature. The fluorocarbons may be present in the polymer as solids or liquids. Chloral'copolymer foams of this invention prepared with these'fluorocarbons resist collapse when the fluorocarbon is evaporated off.

EXAMPLE 104 Copolymers of Chloral and p-Chlorophenyl Isocyanate The following polymerizations were carried out in mm. OD test tubes. To each was added 1.88 ml. of chloral, 0.12 ml. of p-chlorophenyl isocyanate and 8 ml. of one of the diluents specified below. Each mixture 0.1p. Hg pressure for 24 hours at room temperature.

Diluent A CCI3CCIF, B c,c|,F i c F(CF2).,CH2CH3 All three pieces were of low density and had shrunk very little on evaporation of the diluent. The final plugs were 12 mm. in diameter and had been 12.6 mm. in diameter before evaporation of the diluent. The piece from B had a density of 0.24 whereas the density of unfoamed copolymer ranges from 1.8 to 2.0.

TABLE VI The following diluents have given foam structures at the diluent/monomer ratios shown.

The following diluents, although closely related to those that worked, caused the gel plug to collapse on evaporation of the diluent.

b. pt. m. pt. No Foam at F113 CC1 FCCIF 48C. 35C. Sll to l/] F214 C Cl F l 12C. 4/1 CF (CH CH 214C. 4/1

INITIATORS The following examples illustrate a number of additional suitable initiators and their method of preparation.

EXAMPLE 105 Tertiary Phosphine/Chloral Reaction Products A. (C H P/CCl Cl-lO 1/ 1 Salt The salt for which H. Hoffman and H. J. Diehr in Tetrahedron Letters, 13, 583 (1962) suggested the structure and which we have substantiated, was prepared as follows:

A solution of 52 g. of triphenyl phosphine in 200 ml. of dry ether was heated to reflux with stirring under dry nitrogen. As a solution of 25 ml. of chloral in 50 ml. of dry ether was added, a white precipitate separated with evolution of heat. The addition required about 10 min. The ether was removed by evaporation in a stream of dry nitrogen overnight at room temperature to leave 78 g. of triphenyldichlorovinyloxyphosphonium chloride. A portion (76 g.) of the product was dissolved under dry nitrogen in about 300 ml. of dichloromethane and filtered under dry nitrogen to remove about 4 g. of insoluble material. The filtrate was evaporated to about 250 ml. and diluted with about ml. of petroleum ether. When only an oil separated, the mixture was evaporated to about 200ml. and then mixed with about 100 ml. of dry diethyl ether. The colorless crystals which formed were collected on a filter under nitrogen and dried to give 48 g. of pure triphenyldichlorovinyloxyphosphonium chloride, m.p. l30-l32C. (dec.).

35 Anal. Calcd. for C H OCI P: C, 58.63; H, 3.94; Cl, 25.96; P, 7.56. Found: C, 58.31; 1H, 3.99; Cl, 25.46; P, 7.47.

Tertiary Phosphine/Bromal Reaction Product B. (C H P/CBr CHO l 1 Salt Using the same procedure as in A, 52 g. of triphenylphosphine and 21 ml. of bromal yielded a 1/ 1 salt product a portion of which was recrystallized from dichloromethane/ether to yield tan crystals, m.p. 135142C. (dec.).

Anal. Calcd. for C H OBr P: C, 44.23; H, 2.98; P, 5.70; Br, 44.15, Found: C, 43.99; H, 3.18; P, 5.91; Br, 44.15.

C. Aliphatic Tertiary Phosphine/Chloral 1/1 Salts As tabulated below, 1/1 salt products were prepared from chloral and a variety of tertiary alkyl phosphines (R P) by the procedure of A above.

- 36 Anal. Calcd. for C H PO C, 80.34; H, 5.62; P, 6.91. Found: C, 77.08;'H, 5.74; P, 6.79.

EXAMPLE 107 Arylaryloxy tertiary Phosphines and Their Sulfur Analogs R P Chloral Yield, g. M.P. Analysis R Amt. ml. of theory) C. ((1) C H P Cl 1. CH 4.8 g. 6.7 13.8 l05130 F 24.40 4.19 12.67 50.31 C 26.88 4.51 13.86 47.60 2. C H 5.5 g. 4.6 11.7 l36139 F 36.09 6.23 11.35 41.91 C 36.18 6.07 11.65 40.05 3. i-C H 16 ml. 27 (90) 1141 16 F 43.85 7.23 9.90 34.40 C 43.93 7.21 10.07 34.57 4. n-C.,H 20 ml. 10 23 105-108 F 49.51 8.51 8.97 29.57 C 48.08 8.08 8.86 30.42 5. t-C.,H 3 g. 1.6 5.1 F 43.35 7.07 8.56 34.53 C 48.08 8,07 8.86 30.42 6. cyclo-C l-l 21 g. 8 18 (67) 140-143 F 55.92 7.92 7.28 25.14 C 56.14 8.01 7.24 24.84

D. Triisopropylphosphine/Chloral 1/ 3 Product To chloral (200 m1.) heated to 60C. under nitrogen was added 1 1.5 g. of triisopropyldichlorovinyloxyphosphonium chloride (from C-3 above). The clear solution was held overnight under nitrogen at 60C. and then poured into 400 ml. of dry ether. The oil which first separated became crystalline on standing at room temperature. The solid was collected under nitrogen and recrystallized by dissolution in 80 ml. of dichloromethane and dilution with 400 ml. of dry ether. The crystalline 3/ 1 chloral/triisopropylphosphine reaction product was collected and dried under dry nitrogen.

Anal. Calcd. for C H O Cl P: C, 29.90; H, 4.01; P, 5.14; CI, 52.97. Found: C, 30.47; H, 4.29; P, 5.16; Cl, 52.92.

EXAMPLE 106 Triphenylphenoxyphosphonium Phenoxide, ts 5)3 s 5l (C6H5O) To a solution of triphenyl dichlorophosphorane (C H PCl (33.3 g.) in 350 ml. of benzene was added at 5C. 20.2 g. of triethyl amine in ml. of benzene followed by a solution of phenol (18.8 g.) in 80 ml. of benzene. The mixture was held at 0C. for 0.5 hr. and at room temperature overnight. The triethylammonium chloride was removed by filtration. Evaporation of the benzene left a semicrystalline residue which when treated with a mixture of cyclohexane, acetone and ether deposited 8 g. of crystalline triphenylphenoxyphosphonium phenoxide which when unionized can be called triphenyldiphenoxyphosphorane.

B. Diphenyl Phenylphosphonite, C H P(OC H To a solution of phenol (38.0 g.) and pyridine 621g.)

in m1. of dry ether was added at 10C. a solution of phenylphosphonous acid dichloride, C H PCl (35.8 g.) in 50 ml. of dry ether. After 1 hr. at 0C., the pyridinium chloride was removed by filtration and the filtrate distilled. The main fraction (33 g.) of diphe'n'yl phenylphosphonite boiled at C. at 0.8 mm.

Anal. fOI' c1 H 5PO2: C, H, p, 10.53. Found: C, 73.38; H 5.39; P, 10.37.

C. p-Tolyl Ester of Diphenylthiophosphinous Acid,- P' a s 4 s 5)2 Di-p-tolyl Phenylthiophosphonite, s 5 JL a-Wz To a solution of p-methylthiophenol p-Cl-l C l-l SH (38 g.) and pyridine (22 ml.) in 100 ml. of dry ether was added at 10C. a solution of phenylphosphonous acid dichloride, C H PCl (27.0 g.) in ether (50 ml.). After 1 hour, the pyridinium chloride was removed by filtration and the filtrate distilled to give 46 g. of di-ptolyl phenylthiophosphonite (p-CH C H S) PC H boiling at C. at 0.4 mm.

37 Anal. Calcd. for C' H PS C, 67.77; H, 5.40; P, 8,74; S, 18.09. Found: C, 68.16; H. 5.66; P, 8,80; S, 18.09. 1

EXAMPLE 108 Substituted Tertiary Aryl Phosphines A variety of trisubstituted phosphines were prepared by adding an ethereal solutionof PCl C H PCI r (C H PCl to an ethereal solution containing 3, 2, or 1 mole, respectively, of an appropriately substituted phenyl Grignard reagent, or in certain cases, the analogous organolithium derivative. The reaction mixture was hydrolyzed with an excess of aqueous ammonium chloride, the organic layer separated and dried over anhydrous magnesium sulfate. Evaporation of the ether left the desired tertiary phosphine which was appropriately distilled or recrystallized depending on its physical properties.

The phosphine initiators made in this way lated below.

are tabu- A. Tri-p-chlorophenylphosphine (p-Cl-C H P The Grignard reagent from 200 g. p-chloroiodobenzene and 20.8 g. of magnesium was reacted with 15.8 ml. phosphorous trichloride to give 39 g. tri(chloro- -phenyl)phosphine, b.p. 228C. at 1 mm., m.p. 103.5C.

ex ethanol.

B. p-Methoxyphenyldiphenylphosphin s s )2PC6H4OCH3'P The Grignard reagent from 59 g. p-iodoanisole and 7.3 g. magnesium was reacted with 44 g. diphenylphosphinous chloride, (C H PCl to give p-methoxyphenyldiphenylphosphine which turned crystalline after distillation.

Anal. Calcd. for C H PO: C, 78.04; H, 5.86; P, 10.60. Found: C, 77.44; H, 6.03; P, 10.10.

Tri-o-methoxyphenylphosphine (o-CH OC H.,) p

The Grignard reagent from 140 g. o-iodoanisole and 17.5 g. of magnesium was reacted with 20.6 g. phosphorous trichloride to give crystalline tri-oqnethoxyphenylphosphine, mp. 203C.

Anal. Calcd. for C H PO C, 71.58; H, 6.01; P, 8.79. Found: C, 71.61; H, 6.12; P, 8,63.

o-Methoxyphenyldiphenylphosphine, (C6H5 )2PC6H4OCH3-O The Grignard reagent from 59 g. o-iodoanisole and 7.3 g. magnesium was reacted with 44 g. of diphenylphosphinous chloride to give 41 g. of diphenyl-omethoxyphenylphosphine, m.p. 122-l23C. ex alcohol.

Anal. Calcd. for C H PO: C, 78.08; H, 5.86; P, 10.60. Found: C, 78.00; H, 5.99; P, 10.24.

E. Tetramesityldiphosphine [(2,4,6-(CH C H )P] The Grignard reagent from 120 g. mesityl bromide and 17.5 g. magnesium was reacted with 20.6 g. phosphorous trichloride to give 27 g. of what is apparently tetramesityldiphosphine, m.p. 240244C. (dec.) ex

' ether.

'F. Mesityldiphenylphosphine (C6H5)2PC6H2(CH3)32,4:6

The Grignard reagent from 50 g. .mesityl bromide and 7.3 g. of magnesium was reacted with 44 g. of diphenyl- 38 phosphinous chloride to give 28.6 g. of diphenylmesitylphosphine, b.p. 175C. at 0.2 mm.

Anal. Calcd. for C H P: C, 82.87; H, 6.96; P, 10.18. Found: C, 81.82; H, 6.96; P, 10.00.

G. Tri(o-meththiomethylphenyl)phosphine (O-CH 3SCH2C6H4 )3!) The organolithium compound from 118 g. o-bromobenzyl methyl sulfide (o-BrC H CH SCH and 380 ml. of a hexane solution containing an equivalent amount of butyllithium was reacted with 16 m1. phosphorous trichloride to give 6 g. of solid tri(o-meththiomethylphenyl) phosphine, m.p. 8990C.

Anal. Calcd. for C H PS C, 65.12; H, 6.15; P, 7.00; S, 21.73. Found: C, 65.48; H, 6.33; P, 7.39; S, 20.37.

H. Diphenyl-o-meththiomethylphenylphosphine, (C6H5 )2PC6H4CH2SCH3-O The organolithium derivative from 21.7 g. of obromobenzyl methyl sulfide (0-BrC H CH SCH and ml. of a 1.6 molar hexane solution of butyllithium was reacted with 18 ml. of diphenylphosphonous chloride to give liquid diphenyl o-meththiomethylphenylphosphine.

Anal. Calcd. for C H, PS: C, 74.51; H, 5.94; P. 9.61; S, 9.95. Found: C, 74.35; H, 6.03; P, 9.30; S, 9.56.

EXAMPLE 109 Triarylaryloxy(or thio)phosphonium Halides A. p-Methylphenylthiotriphenylphosphonium Bromide, p-CH C SP (C HQ Br- To a suspension of 12.3 g. of the triphenylphosphine/cyanogen bromide reaction product in ml. of benzeneat 510C. was added 4.2 g. of p-methyl thiophenol in 15 ml. of benzene to give a clear solution which was then held at 45C. for 15 minutes. Evaporation of the. benzene in vacuo at room temperature left p-rriejthylphenylthiotriphenylphsophonium bromide as an oilwhich turned crystalline on standing at room temperature.

Anal. Calcd. for C 5H PBrS: P, 6.66; S, 6.89. Found: P, 5.61; S, 7.19.

C. Phenoxytriphenylphosphonium Bromide, (C6H5)3POC6H5+ Br- To a suspension of 12.3 g. of the triphenylphosphine/cyanogen bromide reaction product (C H P(CN)Br in 100 ml. of benzene was added at 

1. AMN ADDITION COPOLYMER OF CHLORAL AT LEAST ONE COMONOMER OF THE FORMULA R1R2C=C=O, THE COPOLYMER CONTAINING FROM 1 TO 99.9 MOL PERCENT OF CHLORAL, IN WHICH R1 & R2, ALIKE OR DIFFERENT AND SEPARATELY AND JOINTLY, ARE SELECTED FROM THE GROUP CONSISTING OF
 1. MONOVALENT GROUPS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, CYANO, LOWER ALKOXYCARBONYL, AND UNSUBSTITUTED AND SUBSTITUTED HYDROCARBYL AND HYDROCARBYLOXY IN WHICH ANY HYDROCARBYL MOIETY IS OF 1-18 CARBON ATOMS SELECTED FROM THE GROUP CONSISTING OF ALKYL, CYCLOALKYL, ARYL, ARALKYL AND ALKARYL, AND ANY SUBSTITUENT IS SELECTED FROM THE GROUP CONSISTING OF LOWER ALKOXY, FLUORINE, BROMINE, AND IODINE, AND
 2. DIVALENT GROUPS SELECTED FROM ALKYLENE OF 2 TO 7 CARBONS.
 2. A copolymer of claim 1 in the form of an article of manufacture.
 2. divalent groups selected from alkylene of 2 to 7 carbons.
 3. A copolymer of claim 1 in the form of a film.
 4. A copolymer of claim 1 in the form of a foam.
 5. A copolymer of claim 1 in the form of a fiber.
 6. A copolymer of claim 1 in the form of a sheet.
 7. A copolymer of claim 1 in the form of a pipe.
 8. A copolymer of claim 1 containing an inorganic filler.
 9. A COPOLYMER OF CLAIM 8 IN WHICH THE FILLER IS FIBER GLASS.
 10. A copolymer of claim 1 stabilized against weight loss from heat.
 11. A copolymer of claim 1 containing from about 50 to 99.9 mol percent of chloral.
 12. A copolymer of claim 1 containing from about 80 to 99.9 mol percent of chloral.
 13. A copolymer of claim 12 wherein the comonomer is diphenylketene.
 14. A copolymer of claim 12 wherein the comonomer is butylethylketene.
 15. A copolymer of claim 12 wherein the comonomer is dimethylketene.
 16. A copolymer of claim 12 wherein the comonomer is pentamethyleneketone.
 17. A copolymer of claim 12 wherein the comonomer is ketene.
 18. A copolymer of claim 12 wherein the comonomer is methylketene.
 19. The cryotachensic polymerization process of making a copolymer of claim 1 comprising chloral and at least one comonomer ketene, comprising forming, at a temperature above its threshold polymerization temperature, a quiescent homogeneous mixture of the monomers and an effective amount of an anionic polymerization initiator, cooling the quiescent mixture below its threshold polymerization temperature to effect polymerization of the monomers, and maintaining the mixture quiescent during the polymerization process.
 20. The process of claim 19 carried out in the presence of an aprotic solvent which is inert to the monomers and initiator and is liquid at the polymerization temperature.
 21. The process of claim 19 wherein the aprotic solvent is a hydrocarbon.
 22. The process of claim 19 wherein the aprotic solvent is a halogenated hydrocarbon.
 23. The process of claim 19 wherein the process is carried out in a mold to produce a shaped copolymer.
 24. The cryotachensic polymerization process of making a copolymer of claim 1 comprising chloral and at least one comonomer ketene, comprising forming, at a temperature above its threshold polymerization temperature, a quiescent homogeneous mixture of chloral and an effective amount of an anionic polymerization initiator, cooling the quiescent mixture below its threshold polymerization temperature to effect homopolymerization of part of the chloral under quiescent conditions, and then adding the at least one comonomer as set out above and causing it to copolymerize with at least the remaining free chloral.
 25. The process of claim 24 in which about 60 percent of the original quantity of chloral is polymerized to homopolymer under quiescent conditions.
 26. An unpolymerized liquid mixture of chloral and at least one compound the formula
 27. A liquid mixture of claim 26 containing from about 50 to 99.9 mol percent of chloral.
 28. A liquid mixture of claim 26 containing from about 80 to 99.9 mol percent of chloral.
 29. A liquid mixture of claim 28 containing 0.001 to 10% by weight of the combined weight of chloral and comonomer(s) present, of an anionic polymerization initiator, said unpolymerized liquid mixture being maintained above its threshold polymerization temperature.
 30. A liquid mixture of claim 28 containing 0.01 to 70% by weight of an inorganic filler.
 31. A liquid mixture of claim 28 containing diphenylketene as a comonomer. 